An official from Mr Taylor's National Patriotic Party said the news was "shocking".

Mr Obasanjo has always refused to send Mr Taylor to Sierra Leone, saying he would only extradite him following a request from an elected Liberian leader.

Ellen Johnson-Sirleaf took power in Liberia in January after winning last year's elections and visited Nigeria earlier this month.

Mrs Johnson-Sirleaf has previously said her priority is rebuilding Liberia, rather than putting Mr Taylor on trial.

But before she briefed the UN Security Council in New York on the situation in Liberia, she confirmed the request, reports the AFP news agency.

"I asked the African (Union) leadership to bring the Taylor issue to closure," she said.

Immunity

Mr Taylor is accused of selling diamonds and buying weapons for Sierra Leone's Revolutionary United Front rebels, who were notorious for hacking off the hands and legs of civilians during a 10-year war.